ICP Defrost Control Board for YC036F — Heat Pump Defrost Timer | Ships Today

Overview

The ICP defrost control board (OEM part 34332100) manages the defrost cycle on your YC036F heat pump. It reads the outdoor coil temperature sensor and a timing interval, then energizes the reversing valve and stops the outdoor fan to clear frost from the coil in cold weather. A failed board causes one of two problems: the coil ices over and never defrosts (lost heating capacity), or the unit defrosts far too frequently (short cycling and high energy bills). Running on a 24V control signal, the board houses the relays and logic that coordinate the compressor, outdoor fan, and reversing valve through each defrost event.

Specifications

Compatibility

Factory replacement for the ICP YC036F heat pump and other Tempstar, Heil, and Comfortmaker units originally built with defrost board 34332100. Match the printed part number on your old board before installing.

Installation Guide

1. Safety First — Disconnect power at the disconnect and breaker, verify zero voltage with a multimeter.
2. Access — Remove the outdoor unit's electrical access panel.
3. Document — Photograph every wire and terminal position before disconnecting.
4. Remove — Label and unplug the low-voltage connectors and sensor leads, then unscrew the failed board from its standoffs.
5. Install — Mount the new 34332100 board, reconnect each wire exactly per your photo, and seat the defrost sensor on the coil tube.
6. Test — Restore power and observe a defrost cycle to confirm the reversing valve and fan respond.

Signs You Need a Replacement

• Outdoor coil ices over and never clears in heat mode
• Unit defrosts too often (short cycling, frequent steam clouds)
• Reversing valve or outdoor fan won't switch during defrost
• Burnt traces, scorched relays, or corrosion on the board

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.